What to know: Pa. school stabbing suspect Alex Hribal

Twenty students and a security officer were either stabbed or slashed during a rampage at a high school in Murrysville, Pa., on Wednesday. The stabbing suspect has been identified as 16-year-old Alex Hribal.

Twenty students and a security officer were either stabbed or slashed during a rampage at a high school in Murrysville, Pa., Wednesday. The stabbing suspect has been identified as 16-year-old Alex Hribal. Learn more about Hribal and how the community is reacting to the horrific attack.